Disposable Diapers have met with increased commercial acceptance in recent years, primarily because of their convenience as opposed to cloth diapers which need to be laundered when once soiled. Many different constructions have been proposed and some have met with widespread commercial acceptance in spite of certain inadequacies in commercial properties.
Also, in recent years, disposable diapers having elastic or leg-encircling portions have also entered the market, and even though being more costly to produce and more expensive to the consumer, still have gained acceptance in the disposable diaper market.
Examples of such stretch or elastic disposable diapers are described in U.S. Pat. Nos. 3,860,003 and 4,050,462. Also, in U.S. Pat. No. 4,801,301 there is shown one method and apparatus for making disposable diapers that have elasticized or stretchable leg-encircling portions. Furthermore, in a recently issued U.S. Pat. No. 4,227,952, there is shown yet another method and apparatus for making diapers with elastic bands in them.
The economics in the manufacture of disposable diapers is extremely important and disposable diapers must be made at fast rates of speed with low cost materials and in the most efficient manner with the least amount of waste in order to produce a product that is accepted in the marketplace from the price standpoint. In view of this, it becomes very important to develop methods and apparatus for accomplishing these purposes, and the simpler and more reliable the method and apparatus, the more economical will be the manufacturing operations.
In the manufacture of stretchable or elasticized disposable diapers, one of the most important parameters is to produce diapers that consistently have the same amount of stretch or elasticity in their leg-encircling portions and also to produce individual diapers that have the same elasticity or stretchability in both of their leg-encircling portions.